If you're a vain male who thinks highly of themselves and hot girls, go for Muffy. If you're a depressed male who thinks dark thoughts and likes to be alone, go for Nami. And if you're a "nature boy" who likes animals and plants, go for Celia.

I vote Celia, even though Nami really suits MY personality better (even though I'm not a depressed male who thinks dark thoughts and likes to be alone XD), but I never married Nami in this game, so I don't know how good a mom is. Celia, on the other hand, is a much better mom than Muffy, IMO.